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nucleolus

(noo-KLEE-uh-lus)
An area inside the nucleus of a cell that is made up of RNA and proteins and is where ribosomes are made. Ribosomes help link amino acids together to form proteins. The nucleolus is a cell organelle.
Drawing showing a cell containing organelles, including the nucleus (contains DNA), the nucleolus, Golgi complex, mitochondria, and endoplasmic reticulum. Also shown are the cell membrane and a membrane receptor.Enlarge this image in new window
Parts of a cell. A cell is surrounded by a membrane, which has receptors on the surface. A cell has several small structures inside it, including the nucleus, mitochondria, endoplasmic reticulum, and Golgi complex. These all have specific functions in the cell.
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